Eikonal profile functions and amplitudes for pp\rm pp and pˉp\bar{\rm p}{\rm p} scattering

The eikonal profile function $J(b)$ obtained from the Model of the Stochastic Vacuum is parametrized in a form suitable for comparison with experiment. The amplitude and the extended profile function (including imaginary and real parts) are determined directly from the complete pp and $\bar{\rm p}$p elastic scattering data at high energies. Full and accurate representation of the data is presented, with smooth energy dependence of all parameters. The changes needed in the original profile function required for description of scattering beyond the forward direction are described.Comment: Latex, 28 pages and 16 figure

Evidence for eikonal zeros in the momentum transfer space

We present the results of fitting elastic $pp$ differential cross section data at 23.5 $\leq \sqrt{s} \leq$ 62.5 GeV with a novel analytic parametrization for the scattering amplitude. Making use of a fitting method, the errors from the free parameters are propagated to the imaginary part of the eikonal in the momentum transfer space. A novel systematic study of the effects coming from data at large momentum transfer is also performed. We find statistical evidence for the existence of eikonal zeros in the interval of momentum transfer 5-9 $GeV^{2}$.Comment: Text with 9 pages in Revtex (preprint form), 8 figures in PostScript. Replaced with small changes. Final version to be published in Physical Review

Proposal to study multiparticle-peripheral hadron physics at NAL

We propose to build a large wire chamber magnetic spectrometer at NAL to measure multi-body forward-going hadronic systems produced by {pi}'s, K's and protons up to 80 GeV/c. Specific reactions will be isolated in order to study the s and t dependencies of the cross sections for peripheral processes, search for new resonant states and attempt to measure {pi}{pi} and K{pi} inelastic scattering. We propose a physics program for the spectrometer which is initially limited to those processes easiest to measure and which nevertheless spans a large range of strong interaction problems. Technically, the proposed spectrometer is a relatively modest extension of presently operating systems in the 10-20 GeV/c region, and does not present a challenge of uncertain magnitude to construct

The practical Pomeron for high energy proton collimation

We present a model which describes proton scattering data from ISR to Tevatron energies, and which can be applied to collimation in high energy accelerators, such as the LHC and FCC. Collimators remove beam halo particles, so that they do not impinge on vulnerable regions of the machine, such as the superconducting magnets and the experimental areas. In simulating the effect of the collimator jaws it is crucial to model the scattering of protons at small momentum transfer t, as these protons can subsequently survive several turns of the ring before being lost. At high energies these soft processes are well described by Pomeron exchange models. We study the behaviour of elastic and single-diffractive dissociation cross sections over a wide range of energy, and show that the model can be used as a global description of the wide variety of high energy elastic and diffractive data presently available. In particular it models low mass diffraction dissociation, where a rich resonance structure is present, and thus predicts the differential and integrated cross sections in the kinematical range appropriate to the LHC. We incorporate the physics of this model into the beam tracking code MERLIN and use it to simulate the resulting loss maps of the beam halo lost in the collimators in the LHC

Search for narrow resonances in the R region

The authors report on a measurement of the missing-mass, (mm)/sup -/, spectrum from the reaction pi /sup -/+p to (mm)/sup -/+p at 8 GeV. The data contain 6500 events in the R peak (M/sup 2/=2.72+or-0.02 GeV/sup 2/, Gamma =139+or-31 MeV). The R shape is consistent with either a single Breit-Wigner or several wide resonances, as suggested by bubble-chamber experiments, but inconsistent with the series of narrow resonances reported by the CERN missing-mass group. (8 refs)

Measurements of missing mass (MM) spectra from pi /sup -/p to (MM)/sup -/p at 8, 11, 135, and 16 GeV

The MM mass range examined is 0<or=M/sup 2/<or=7.3 GeV/sup 2/ with t (the proton four momentum transfer squared) in the interval 0.2<or= mod t mod <or=0.3 GeV/sup 2/. Narrow resonances (R/sub 1/, R/sub 2/, R /sub 3/, S, T, and U) with cross sections and widths reported by the CERN missing mass group are ruled out by the data. The cross sections d/sup 2/ sigma /dtdM/sup 2/ show evidence for triple factorizability of the form d/sup 2/ sigma /dtdM/sup 2/ approximately=D(P/sub B/)A(M /sup 2/)G(P/sup 2/) where P/sub B/ is the incident beam momentum, and P/sup 2/ is the perpendicular component of the detected proton's momentum with respect to the beam direction. (19 refs)